The website is in Japanese, so there isn't much information to us English speakers, but here's some rough Google translation answering the question, "What is the game Star Galaxy?"

"Star Galaxy" is a simulation strategy game that takes place in the galaxy.Enhance the military to develop the territory of planet that is home to organize our officers were brought up to their liking, emergency, fighting to the sector.In cooperation with the friendly, self-force will lead to victory.

So, there you go. Simulation strategy in space. It will be entering beta soon and hopefully we will have more general information about the game soon.

Update: According to rumor (and our comments section) it looks like Star Galaxy is a browser game. The best evidence so far to confirm this rumor is that the system requirements list assorted Internet browsers and the latest version of Flash. Is this something you are excited about checking out?